Confined Electron: Min Uncertainty in Momentum/Velocity

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The discussion centers on calculating the minimum uncertainty in the momentum and velocity of an electron confined in a quantum wire of 150 nm. The uncertainty principle is applied, specifically the relation between position and momentum uncertainties. The user initially calculates the uncertainty in momentum but arrives at an incorrect value. There is confusion regarding the correct application of the uncertainty principle, particularly whether to use h or h/2π. Clarification on these calculations is sought to resolve the issue.
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Homework Statement


An electron is confined to a "quantum wire" of length 150 nm. what is the minimum uncertainty in the electron's momentum component along the length of the wire? What is the minimum uncertainty in the electron's velocity component along the length of the wire?


Homework Equations


(uncertainty in x coordinate of position)(uncertainty in x component of momentum) > or equal to 1/2pi

I used 150 x 10^-9 for change in x and solved but got 3.52 x 10^-28 but this is wrong

how do i do this? thanks

The Attempt at a Solution

 
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(uncertainty in x coordinate of position)(uncertainty in x component of momentum) > or equal to 1/2pi ?

isn't it h/2pi ?
 

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